We recently upgraded from 9.5.1 to 9.5.2 FP2 on Windows 2008 R2 version on 64-bit OS. 9.5.1 was uninstalled first.
It passed UAT but we didn't think to test deploying a new app as part of our testing (how far do you go with testing an upgrade?)

IBM cannot reproduce it so they were reluctant to escalate it to development at first.
Today, they have escalated it and on their request, I sent them the PMPSVC.log, TM1Web.log, logs from BI Server, Fiddler logs and config files.